Vitamin D helps your body absorb calcium. It is necessary for the absorption and metabolism of calcium for the baby’s bone health and preventing osteoporosis in mom. Fetal needs for vitamin D increase during the latter half of pregnancy, when bone growth and ossification are most prominent. It’s also incredibly important to have enough of while breastfeeding. Vitamin D might even help prevent preeclampsia and gestational diabetes. It is also needed to help the body create sex hormones which in turn affects ovulation, hormonal balance, and fertility. Best Sources: 20-30 minutes of sunshine, wild salmon, wild sardines, organic eggs, dairy from grass-fed cows.